Photoshop-style bitmap image editors work with pixels, and therefore require large file sizes in order to preserve resolution. By comparison, vector-based illustrations are lightweight and able to scale up or down without a loss in quality, but finding quality App Store solutions for creating and editing such files can be a challenge. One such option is Inkpad, which has now gone from paid to free with the most recent release – and not the kind of free that involves in-app purchases to be useful. Instead, developer Taptrix made the app open source, allowing others to build upon its work and contribute to future versions.